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保山北庙水库集水区5种森林类型枯落物持水特性研究

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长江科学院院报 2015年第1期32卷 43-48页

作者：沈盈佳曾建军云南师范大学旅游与地理科学学院昆明650500

利用样方调查法、烘干法、浸泡法分析了云南省保山市北庙水库集水区纯云南松、纯人工桉树林、混交林Ⅰ(云南松+桉树混交林)、混交林Ⅱ(云南松+华山松+杉木+青冈栎混交林)和纯华山松5种森林类型枯落物的持水能力。结果表明:5种森林类型... 详细信息

利用样方调查法、烘干法、浸泡法分析了云南省保山市北庙水库集水区纯云南松、纯人工桉树林、混交林Ⅰ(云南松+桉树混交林)、混交林Ⅱ(云南松+华山松+杉木+青冈栎混交林)和纯华山松5种森林类型枯落物的持水能力。结果表明:5种森林类型枯落物蓄积量都较小,最大为7.27 t/hm2,最小为4.51 t/hm2;枯落物未分解层和半分解层持水量随着浸泡时间增加,在8 h时平均持水量分别为5.22,5.83 t/hm2,24 h时分别为5.69,6.26 t/hm2;吸水速率随着浸泡时间减少,在8 h时平均吸水速率分别为0.65,0.73 mm/h,到24 h时分别为0.24,0.26 mm/h,且均是半分解层>未分解层;纯华山松和混交林Ⅱ2种森林类型枯落物持水性能优于其他3种森林类型。研究结果可为水源区植被恢复、选择最佳树种、合理配植森林类型、森林涵养水源提供科学依据。

关键词：北庙水库森林枯落物最大持水量最大拦蓄量有效拦蓄量

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie Zhi-Liang Qin jian-Hua Wang Peng Song Heng-Guang Shen Sheng-Qi Yu Ben-jun Ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

Widely-wavelength-tunable brillouin fiber laser with improved optical signal-to-noise ratio based on parity-time symmetric and saturable absorption effect

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中国光学（中英文） 2024年第5期17卷 1244-1253页

作者： LIU Yi jianG Kai FANG Xin-yue YOU Ya-jun HE Wen-jun HOU Jia-xin HAN Xue-feng CHOU Xiu-jian State Key Laboratory of Dynamic Measurement Technology School of Instrument and ElectronicsNorth University of ChinaTaiyuan 030051China School of Aerospace Engineering North University of ChinaTaiyuan 030051China Shanxi Province Key Laboratory of Quantum Sensing and Precision Measurement North University of ChinaTaiyuan 030051China

A widely-wavelength-tunable Brillouin fiber laser(BFL)with improved optical signal-to-noise ratio(OSNR)based on parity-time(PT)symmetric and saturable absorption(SA)effect is *** novel BFL realizes PT symmetry and SA effect through polarization-maintaining erbium-doped fiber(PM-EDF)Sagnac loop,which is composed of a PM-EDF,a coupler and two polarization controllers(PCs).By using the inherent birefringence characteristic of PM-EDF,two feedback loops in orthogonal polarization state are formed when the Strokes signal in *** of these loops provides gain in the clockwise direction with in the Sagnac loop,while the other loop generates loss in the counterclockwise *** adjusting the PCs to control the polarization state of the PM-EDF,a single-longitudinal-mode(SLM)BFL can be achieved,as the PT symmetry is broken when the SA participating stimulated Brillouin scattering(SBS)gain and loss are well-matched and the gain surpasses the coupling *** to previous BFLs,the proposed BFL has a more streamlined structure and a wider wavelength tunable range,at the same time,it is not being limited by the bandwidth of the erbium-doped fiber amplifier while still maintaining narrow linewidth SLM ***,thanks to SA effect of the PM-EDF,the PT symmetric SBS gain contract is enhanced,resulting in a higher optical signal-to-noise(OSNR).The experimental results show that the laser has a wide tunable range of 1526.088 nm to 1565.498 nm,an improved OSNR of 77 dB,and a fine linewidth as small as 140.5 Hz.

关键词： Brillouin fiber laser widely-wavelength-tunable parity-time symmetric high OSNR narrow linewidth

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Turbo乘积码在卫星通信中的应用分析

微型电脑应用 2009年第12期25卷 15-16,20页

作者：曾剑隽上海交通大学计算机科学与工程系

Turbo乘积码在卫星通信中起到很强的纠错作用,其编译码性能的好坏直接影响到卫星通信信号的传输质量。通过对Turbo乘积码Chase译码算法的分析和改进,得出了译码算法中各个参数的选择对译码性能的影响的仿真实验结果,并对实际的卫星通信... 详细信息

Turbo乘积码在卫星通信中起到很强的纠错作用,其编译码性能的好坏直接影响到卫星通信信号的传输质量。通过对Turbo乘积码Chase译码算法的分析和改进,得出了译码算法中各个参数的选择对译码性能的影响的仿真实验结果,并对实际的卫星通信信号进行仿真实验,对仿真结果进行性能分析,验证了Turbo乘积码可以得到很好的译码结果。

关键词： Turbo乘积码卫星通信 Chase算法性能分析

Electronic engineering of Co-Ru diatomic sites and Ru nanoparticles for synergistic promotion of hydrogen evolution

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Nano Research 2024年第5期17卷 3714-3723页

作者： Wei Zhang Cong Li Yongyong Cao jun-Yang Ji Zhao-Chen Li Zheng Niu Hongwei Gu Pierre Braunstein jian-Ping Lang College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China College of Biological Chemical Science and EngineeringJiaxing UniversityJiaxing 314001China Universitéde Strasbourg-CNRS Institut de Chimie(UMR 7177 CNRS)4 rue Blaise Pascal-CS 9003267081 StrasbourgFrance

The coexistence of multi-component active sites like single-atom sites,diatomic sites(DAS)and nanoclusters is shown to result in superior performances in the hydrogen evolution reaction(HER).Metal diatomic sites are more complex than single-atom sites but their unique electronic structures can lead to significant enhancement of the HER *** the synthesis and identification of DAS is usually challenging,we report a simple access to a diatomic catalyst by anchoring Co-Ru DAS on nitrogen-doped carbon supports along with Ru nanoparticles(NPs).Experimental and theoretical results revealed the atomic-level characteristics of Co-Ru sites,their strong electronic coupling and their synergy with Ru NPs within the *** unique electronic structure of the catalyst resulted in an excellent HER activity and stability in alkaline *** work provides a valuable insight into a widely applicable design of diatomic catalysts with multi-component active sites for highly efficient HER electrocatalysis.

关键词： Co-Ru diatomic sites Ru nanoparticles multiple active sites synergistic effect hydrogen evolution reaction

Multi-omics analysis of human tendon adhesion reveals that ACKR1-regulated macrophage migration is involved in regeneration

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Bone Research 2024年第2期12卷 390-406页

作者： Xinshu Zhang Yao Xiao Bo Hu Yanhao Li Shaoyang Zhang jian Tian Shuo Wang Zaijin Tao Xinqi zeng Ning-Ning Liu Baojie Li Shen Liu Department of Orthopaedics Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine600 Yishan RdShanghai 200233PR China Section of Spine Surgery Department of OrthopaedicsChangzheng HospitalNaval Medical UniversityShanghai 200003PR China Bio-X Institutes Key Laboratory for the Genetics of Developmental and Neuropsychiatric DisordersMinistry of EducationShanghai Jiao Tong UniversityShanghai 200241PR China Department of Orthopaedics Wuxi Ninth People’s Hospital Affiliated to Soochow UniversityWuxi 214062PR China State Key Laboratory of Systems Medicine for Cancer Center for Single-Cell OmicsSchool of Public HealthShanghai Jiao Tong University School of MedicineShanghai 200025China

Tendon adhesion is a common complication after tendon injury with the development of accumulated fibrotic tissues without effective anti-fibrotic therapies,resulting in severe *** are widely recognized as a fibrotic trigger during peritendinous adhesion ***,different clusters of macrophages have various functions and receive multiple regulation,which are both still *** our current study,multi-omics analysis including single-cell RNA sequencing and proteomics was performed on both human and mouse tendon adhesion tissue at different stages after tendon *** transcriptomes of over 74000 human single cells were *** results,we found that SPP1^(+)macrophages,RGCC^(+)endothelial cells,ACKR1^(+)endothelial cells and ADAM12^(+)fibroblasts participated in tendon adhesion ***,despite specific fibrotic clusters in tendon adhesion,FOLR2^(+)macrophages were identified as an antifibrotic cluster by in vitro experiments using human ***,ACKR1 was verified to regulate FOLR2^(+)macrophages migration at the injured peritendinous site by transplantation of bone marrow from Lysm-Cre;R26R^(tdTomato) mice to lethally irradiated Ackr1^(-/-)mice(Ackr1^(-/-)chimeras;deficient in ACKR1)and control mice(WT chimeras).Compared with WT chimeras,the decline of FOLR2^(+)macrophages was also observed,indicating that ACKR1 was specifically involved in FOLR2^(+)macrophages *** together,our study not only characterized the fibrosis microenvironment landscape of tendon adhesion by multi-omics analysis,but also uncovered a novel antifibrotic cluster of macrophages and their *** results provide potential therapeutic targets against human tendon adhesion.

关键词： tendon analysis landscape

Annealing-induced gradient nanostructured FeCrAlTiMo high-entropy alloy coatings with significantly enhanced wear resistance

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Tungsten 2024年第3期6卷 544-548页

作者： jian Yang Ming-Yang Zhou Ji-jun Yang Key Laboratory of Radiation Physics and Technology of Ministry of Education Institute of Nuclear Science and Technology Sichuan University Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China

Recently, the amorphous high-entropy alloy(HEA) coatings exhibit an impressive resistance to the lead–bismuth eutectic(LBE) corrosion and ion irradiation, showing great application potential for lead-cooled fast reac...

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调频式红外干扰机机理研究

激光与红外 2000年第1期30卷 36-38页

作者：曾建军伍长銮李铭王学恩西安电子科技大学技术物理系西安710071

红外有源欺骗式干扰机是对付红外点源制导导弹的有效手段之一。本文根据对干扰调频制导导弹系统的欺骗式干扰机理的研究,建立了针对调频制导导弹的干扰的数学模型,并对目标方位误差信号进行分析。

关键词：红外对抗红外干扰机红外制导导弹

Negative feedback regulation of PROG1 in rice

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Journal of Integrative Agriculture 2024年第9期23卷 3234-3237页

作者： Jinlin Bao Jing Huang Xiaoqing Yang Xizhi Li Shengjie Cheng Wei Huang jun Wang jian Jin State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources Nanning 530004China College of Life Science and Technology Guangxi UniversityNanning 530004China College of Life Sciences South China Agricultural UniversityGuangzhou 510642China National Key Laboratory of Plant Molecular Genetics/Center for Excellence in Molecular Plant Sciences Chinese Academy of Sciences(CAS)/Institute of Plant Physiology and EcologyCASShanghai 200032China

Cultivated rice(Oryza sativa L.),one of the most widely grown and important crops worldwide,is believed to have been domesticated from the ancestral wild rice(Oryza rufipogon Griff.)thousands of years ago(Cheng et al.... 详细信息

关键词： Oryza crops Cultivated